I want to know how to change things about an object taken as a parameter

a simple example would be if I made Angle Changer object

AngleChanger has an actionChange Angle

it gives a drop down list, where you can choose a sprite

and when that action triggers at runtime it changes the angle of the sprite

obviously useless, and more of a behaviorbut, for learning sakewhat would the C++ line of code be that changed the parameter object to a new angleand could I use the same method to change a variable in an object I made with the sdk?